Victor Eduardo de Souza Batista

Purpose: This study aimed to evaluate the effect of internal wall inclination of Morse taper dental implants on the stress distribution on the peri‐implant area, using the photoelasticity method. Materials and Methods: The analysis of stress was performed in three groups (EH: External Hexagon, MT: Morse Taper, GM: Grand Morse), dividing the photoelastic models between implants with external (HE) and internal (MT and GM) connections. Two different inclinations of the internal walls were assessed for implants with internal connection: MT: 11.5° and Grand Morse: 16°. The implant‐supported prostheses were submitted to 100 N axial and oblique loads within the photoelastic models. The qualitative analysis was performed by describing the fringes formed in the photoelastic block. The quantitative analysis of the stresses was performed using the table recommended by the ASTM D4093‐95 standard, which relates the colors of the isochromatic fringes to the numerical stress values. Results: The results showed that the HE had a greater concentration of stresses in the apical region, while the implants with internal connections (MT and GM) showed a similar biomechanical pattern of stress distribution, regardless of the inclination of the internal walls. Conclusions: Increasing the internal wall inclination from 11.5° to 16° did not yield any additional biomechanical advantages in implant‐supported rehabilitation.

The use of herbal medicines has gained popularity, both in science and among the public, as a natural alternative for the treatment of numerous diseases, including type 2 diabetes. Objective: The objective of this study was to evaluate peri-implant and long bone biomechanics in type 2 diabetic animals, treated or not with Bauhinia forficata. Methods: Thirty-two rats were allocated into four groups: normoglycemic (NG), normoglycemic + Bauhinia forficata (NGBf), type 2 diabetes (T2D), and T2D + Bauhinia forficata (T2DBf). Diabetes was induced using a cafeteria diet and streptozotocin (35 mg/kg). Bauhinia forficata tea (50 g/L) was administered to the NGBf and T2DBf groups. After 14 days, titanium implants were installed in the tibial metaphysis of all animals. Biomechanical analysis (removal torque), computerized microtomography, three-point bending test, confocal microscopy, and real-time PCR were performed. The results were tabulated, and a statistical test was conducted with a significance level of 5%. Results: Bauhinia forficata significantly improved the weight and blood glucose levels of the animals. In terms of biomechanics and the microarchitecture of long bones, T2D did not impair bone metabolism, and the use of the therapy did not cause significant changes in the parameters evaluated. However, T2D promoted significant impairment in the structural, biomechanical, and molecular characteristics of the peri-implant repair process, and the use of Bauhinia forficata increased the parameters evaluated in T2DBf. Conclusions: Type 2 diabetes mellitus significantly compromises peri-implant bone repair, with no influence on the metabolism of long bones, and Bauhinia forficata acts positively on both the etiopathogenesis of the disease and the tissue response to bone repair.

Tissue engineering creates possibilities for promoting bone regeneration, which can culminate in an ideal therapy for treating bone defects. Considering its tools, especially exosomes (Exos), inferring its efficiency is fundamental for future clinical protocols. Therefore, this research aimed to analyze, through a systematic review, the effectiveness of Exos therapy for regenerating bone. The study followed the PRISMA, and an electronic search for literature was performed until January 2024 to answer the PICO question: Would exosome therapy be effective for bone regeneration? Bone regeneration and cellular and molecular mechanisms were included in primary and secondary outcomes, respectively. The dosage, route of administration, and source cells have also been reported. The risk of bias was investigated according to the criteria of SYRCLE's RoB tool. The meta-analysis was executed using the standardized mean difference for bone mineral density (BMD) and volume ratio bone/whole bone (BV/TV) for cranial bone defects. A total of 3718 were examined, and after applying the eligibility criteria and excluding duplicates, 91 articles were included in the results. All studies demonstrated that Exos were effective in promoting regeneration of bone defects, being superior to the control groups established by each study included in this review, in most cases. The meta-analysis proved the superiority of Exos when BMD and BV/TV were analyzed. An increase in the levels of Runx2, ALP, OCN, OPN, CD31, COL-1, and VEGF, and presence of osteoblasts, M2-type macrophages, and endothelial cells, indicating osteogenic and angiogenic molecular and cellular mechanisms. The mesenchymal stem cells are the most commonly used origin cells. Exos dosage was varied, associated with scaffolds or hydrogels for application in bone defects. The risk of bias identified high scientific evidence for most domains. The Exos therapy is effective for bone regeneration and shows promise for this purpose.

The use of methods to promote tissue regeneration has been widely used in implantology in clinical situations where there are bone deficiencies and anatomical limitations to install implants. The evolution of biomaterials has facilitating clinical resolution for the installation of implants with a safe and reliable prognosis. The advantage is to promote greater comfort, function and aesthetics, in addition to preserving the surrounding soft tissues. This clinical report illustrates an implant supported rehabilitation using bovine grafting to promote guided bone regeneration (GBR) in the same chair time and resulting in osseointegration of the implants. The patient received cone-morse dental implants in the anterior maxilla, and bovine biomaterial (Bio-Oss®) protected by a resorbable collagen membrane. After installing the implants, immediate provisionals were made and after the osseointegration period, second-stage surgery was performed and new provisionals were made. The definitive prosthesis was finalized involving other adjacent elements as previous clinical planning. We conclude that the GBR technique contributed to the successful treatment and osseointegration of the titanium implants besides improvement of soft contour of anterior region. The patient was satisfied in terms of aesthetics and function.

O objetivo é apresentar um caso de tratamento estético com restauração adesiva indireta do tipo onlay, em cerâmica, para reabilitação unitária de dente com perda de estrutura coronária proveniente de trica. Selecionou-se um paciente na clínica da Faculdade UNOESTE (campus de Presidente Prudente-SP) com destruição coronária em molar com tratamento endodôntico. Optou–se pela restauração indireta do tipo onlay para a reabilitação coronária. Foram realizadas quatro sessões até a finalização do tratamento. Na primeira sessão fez-se raspagem, profilaxia, orientação de higiene bucal, remoção da restauração em resina composta e instalação do pino de fibra de vidro. Na segunda sessão realizou-se preparo do dentel, moldagens, seleção da cor, confecção da restauração provisória e registro da mordida em articulador semi-ajustável. Na terceira sessão realizou-se a cimentação da peça protética, ajuste da oclusão, polimento e moldagens para confecção da placa estabilizadora oclusal. Por fim, na quarta sessão, a placa foi instalada e ajustada. O tratamento estético com restauração adesiva indireta tipo onlay e utilização de placa estabilizadora oclusal seguida da reabilitação de dente com perda de estrutura coronária demonstrou resultado íntegro, estético e funcional satisfatório após dois anos de acompanhamento do caso.

Purpose: The purpose of this 3D finite element analysis was to evaluate the biomechanical effects of different materials used to fabricate occlusal devices to achieve stress distribution in simulated abutment screws, dental implants, and peri‐implant bone tissue in individuals who clench their teeth.Materials and Methods: Eight 3D models simulated a posterior maxillary bone block with three external hexagon implants (Ø4.0 × 7.0 mm) supporting a 3‐unit screw‐retained metal‐ceramic prosthesis with different crown connection (splinting), and the use of an occlusal device (OD). The OD was modeled to be 2‐mm thick. ANSYS 19.2 software was used to generate the finite‐element models in the pre‐and post‐processing phases. Simulated abutment screws and dental implants were evaluated by von Mises stress maps, and simulated bone was evaluated by maximum principal stress and microstrain maps by using a finite element software program.Results: The highest stress values in the dental implants and screws were observed in single crowns without OD (M1). Furthermore, the highest stress values and bone tissue strain were found in single crowns without OD (M1). The simulated material for the OD did not cause many discrepancies in terms of the stress magnitude in the simulated dental implant and abutment screw for both single and splinted crowns; however, more rigid materials exhibited lower stress values.Conclusion: The use of OD was effective in reducing stress in the simulated implants and abutment screws and stress and strain in the simulated bone tissue. The material used to simulate the OD influenced the biomechanical behavior of implant‐supported fixed prostheses, whereas splints with rigid materials such as PEEK and PMMA exhibited better biomechanical behavior.

Purpose: To evaluate the tendency of movement, stress distribution, and microstrain of single‐unit crowns in simulated cortical and trabecular bone, implants, and prosthetic components of narrow‐diameter implants with different lengths placed at the crestal and subcrestal levels in the maxillary anterior region using 3D finite element analysis (FEA).Materials and methods: Six 3D models were simulated using Invesalius 3.0, Rhinoceros 4.0, and SolidWorks software. Each model simulated the right anterior maxillary region including a Morse taper implant of Ø2.9 mm with different lengths (7, 10, and 13 mm) placed at the crestal and subcrestal level and supporting a cement‐retained monolithic single crown in the area of tooth 12. The FEA was performed using ANSYS 19.2. The simulated applied force was 178 N at 0°, 30°, and 60°. The results were analyzed using maps of displacement, von Mises (vM) stress, maximum principal stress, and microstrain.Results: Models with implants at the subcrestal level showed greater displacement. vM stress increased in the implant and prosthetic components when implants were placed at the subcrestal level compared with the crestal level; the length of the implants had a low influence on the stress distribution. Higher stress and strain concentrations were observed in the cortical bone of the subcrestal placement, independent of implant length. Non‐axial loading influenced the increased stress and strain in all the evaluated structures.Conclusions: Narrow‐diameter implants positioned at the crestal level showed a more favorable biomechanical behavior for simulated cortical bone, implants, and prosthetic components. Implant length had a smaller influence on stress or strain distribution than the other variables.

Introduction Narrow diameter implants biomechanics knowledge indicates safe dimensions for clinical use. Objective Purpose of the present study was biomechanically to compare regular and narrow diameter implants to support single implant-supported prosthesis in the anterior region of the maxilla by 3D finite element analysis (3D-FEA). Material and method Four 3D-FEA models were developed form CT scan recompositing and literature data: a bone block in the right upper lateral incisive region with implant and crown. M1: 3.75 x 13 mm, M2: 3.75 x 8.5 mm, M3: 2.9 x 13 mm and M4: 2.9 x 8.5 mm. It was applied load was of 178 N at 0, 30 and 60 degrees in relation to implant long axis. Von Mises stress, maximum principal stress and microdeformation maps were evaluated. Result M3 and M4 did show higher tension and higher microdeformation values than M1 and M2, especially when inclined forces were applied. However, M3 presented enhanced biomechanical behavior than M4. Conclusion It can be concluded that reduce the diameter of the implants can disadvantage to the biomechanics during the application of forces, but the distribution and intensity of the stresses, as well as the micro deformation values can be improved if the length of the implant is increased.

Introduction Periodontal treatment involves procedures aimed to reduce bacterial load, involving or not the use of local or systemic antibiotics. Objective The purpose of this study was to assess Brazilian dentists’ knowledge about antibiotics prescription during periodontal treatment. Material and method An online questionnaire was available asking for systemic application of local or systemic antibiotics prescription (frequency, and sequence with mechanical periodontal treatment) and in relation to different periodontal diseases. The use of microbial diagnostic services and volunteers’ demographic data were also elucidated. Data were statistically analyzed (Binomial Test, p<0.05). Result Three hundred and ninety-three volunteers answered the questionnaire. Twenty-three percent males and 76.2% females. Average age was 27.7 years. Minority (19.2%) of the volunteers reported to indicate systemic antibiotics to treat gingivitis or periodontitis stages I and II (old slight and moderate chronic periodontitis). Majority of the professionals indicate it to treat periodontal abscess, necrotizing ulcerative gingivitis or periodontitis, periodontitis in severe immunodeficiencies, old aggressive periodontitis, and periodontitis stages III and IV (old severe chronic periodontitis). Rarely (2.5%) the prescription was without the combination with mechanical therapy. Microbiological tests as an auxiliary diagnostic method are rarely (3.1%) requested due to lack of information or cost. Most frequent answers about the number of times professionals reported prescribing systemic antibiotics as part of periodontal treatment per trimester was “at least once”, followed by “2 times”. Conclusion It can be concluded that Brazilian dentists have knowledge about the correct prescription of antibiotics in periodontal therapy.

This is an in silico study aimed to evaluate the biomechanical influence of different implant-abutment interfaces (external hexagon and Morse taper implants), retention systems (cement and screw retained), and restorative crowns (metal-ceramic and monolithic) using 3-dimensional finite element analysis (3D-FEA). Eight 3D models were simulated for the maxillary first molar area using InVesalius, Rhinoceros, and SolidWorks and processed using Femap and NEi Nastran software. Axial and oblique forces of 200 and 100 N, respectively, were applied on the occlusal surface of the prostheses. Microstrain and von Mises stress maps were used to evaluate the deformation (cortical bone tissue) and stress (implants/fixation screws/crowns), respectively, for each model. For both loadings, Morse taper implants had lower microstrain values than the external hexagon implants. The retention system did not affect microstrain on the cortical bone tissue under both loadings. However, the cemented prosthesis displayed higher stress with the fixation screw than the external hexagon implants. No difference was observed between the metal-ceramic and zirconia monolithic crowns in terms of microstrain and stress distribution on the cortical bone, implants, or components. Morse taper implants can be considered as a good alternative for dental implant rehabilitation because they demonstrated better biomechanical behavior for the bone and fixation screw as compared to external hexagon implants. Cement-retained prosthesis increased the stress on the fixation screw of the external hexagon implants, thereby increasing the risk of screw loosening/fracture in the posterior maxillary area. The use of metal-ceramic or monolithic crowns did not affect the biomechanical behavior of the evaluated structures.